\put-adjacent only works using Scheme markup

[Neil Puttock]

Hi everybody,

I've been trying to do a snippet for \put-adjacent in
define-markup-commands.scm, but it doesn't work using \markup because
there's no parser tag defined for the signature
MARKUP_HEAD_MARKUP0_SCM1_SCM2_MARKUP3.

I see three options as a solution to this:

1. extend the parser just for this command;

2. pass the Scheme values (axis and direction) as a pair so we can use
MARKUP_HEAD_SCM0_MARKUP1_MARKUP2, which is admittedly rather
inelegant;

3. remove it from define-markup-commands.scm and convert it to a
utility function so it can still be used for figured bass formatting
(though this ignores the remote possiblity that somebody might have
used the command in its Scheme form).

Any thoughts as to the best course of action; possibly one I haven't
thought of? :)

Regards,
Neil